Modifier and modified and conjugated diene-based polymer prepared using the same

ABSTRACT

The present invention provides a modifier including a silane-based compound of Formula 1, which may prevent the agglomeration of a filler in a rubber composition and increase the dispersibility of a filler, thereby improving the processability of a rubber composition, by easily introducing a functional group having affinity with a filler into a conjugated diene-based polymer chain, and a modified and conjugated diene-based polymer prepared using the same.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of priority based on KoreanPatent Application No. 10-2016-0054884, filed on May 3, 2016, the entirecontents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a novel modifier and a modified andconjugated diene-based polymer prepared using the same.

BACKGROUND ART

According to the recent demand for cars having a low fuel consumptionratio, a conjugated diene-based polymer having modulational stabilityrepresented by wet skid resistance as well as low rolling resistance,and excellent abrasion resistance and tensile properties is required asa rubber material for tires.

In order to reduce the rolling resistance of tires, there is a method ofreducing hysteresis loss of vulcanized rubber, and rebound resilience at50° C. to 80° C., tan 5, Goodrich heating, or the like is used as anevaluation index of the vulcanized rubber. That is, it is desirable touse a rubber material having high rebound resilience at the abovetemperature or a low tan 5 value or Goodrich heating.

Natural rubbers, polyisoprene rubbers, or polybutadiene rubbers areknown as rubber materials having low hysteresis loss, but these rubbershave a limitation of low wet skid resistance. Thus, recently, conjugateddiene-based (co)polymers such as styrene-butadiene rubbers (hereinafter,referred to as “SBR”) and butadiene rubbers (hereinafter, referred to as“BR”), are prepared by emulsion polymerization or solutionpolymerization to be used as rubbers for tires. Among thesepolymerization methods, the greatest advantage of the solutionpolymerization in comparison to the emulsion polymerization is that thevinyl structure content and the styrene content, which specify physicalproperties of the rubber, may be arbitrarily adjusted and its molecularweight and physical properties may be controlled by coupling ormodification. Thus, the SBR prepared by the solution polymerization iswidely used as a rubber material for tires because it is easy to changea structure of the finally prepared SBR or BR, and movement of chainterminals may be reduced and a coupling force with a filler such assilica and carbon black may be increased by coupling or modification ofthe chain terminals.

If the solution-polymerized SBR is used as the rubber material fortires, since a glass transition temperature of the rubber is increasedby increasing the vinyl content in the SBR, physical properties such asrunning resistance and braking force, required for tires may becontrolled, and fuel consumption may also be reduced by appropriatelyadjusting the glass transition temperature.

The solution-polymerized SBR is prepared by using an anionicpolymerization initiator and is being used by coupling or modifying THEchain terminals of the polymer thus formed using various modifiers. Forexample, U.S. Pat. No. 4,397,994 discloses a method of coupling activeanions of the chain terminals of a polymer obtained by polymerizingstyrene-butadiene using alkyllithium which is a monofunctional initiatorin a non-polar solvent, using a binder such as a tin compound.

Meanwhile, as a material of a tire tread which comes in contact with theground, a material having low rolling resistance, excellent wet grip,and practically sufficient abrasion resistance, is required.

Generally, carbon black and silica are being used as a reinforcingfiller of a tire tread, wherein, if the silica is used as thereinforcing filler, hysteresis loss may be small and wet skid resistancemay be improved. However, since the silica having a hydrophilic surfacehas a low affinity with a conjugated diene-based rubber in comparison tothe carbon black having a hydrophobic surface, dispersibility may bepoor, and thus, there is a need to use a separate silane coupling agentto improve the dispersibility or provide coupling between the silica andthe rubber.

Therefore, attempt of introducing a functional group having affinity orreactivity with silica into the terminal of a rubber molecule to improvethe dispersibility of silica in a rubber composition, to decrease themobility of the terminal of the rubber molecule via the combination withsilica particles, and to decrease hysteresis loss, is being performed,but its effect is insufficient.

Accordingly, the development of rubbers having high affinity with afiller such as silica is required.

DISCLOSURE OF THE INVENTION Technical Problem

The present invention has been devised in consideration of theabove-mentioned problems, and an object of the present invention is toprovide a modified and conjugated diene-based polymer which is modifiedby a modifier to show excellent affinity with a filler in a rubbercomposition, and at the same time, the mobility of the terminal of arubber molecule is decreased via the combination with a filler todecrease hysteresis loss when applied to a rubber composition for tires.

Another object of the present invention is to provide a method forpreparing the modified and conjugated diene-based polymer.

Further another object of the present invention is to provide a novelmodifier used for the modification of a conjugated diene-based polymer.

Also, further another object of the present invention is to provide arubber composition including the modified and conjugated diene-basedpolymer.

In addition, further another object of the present invention is toprovide a tire manufactured from the rubber composition.

Technical Solution

To solve the above-described tasks, according to an embodiment of thepresent invention, there is provided a modified and conjugateddiene-based polymer modified by a modifier including a silane-basedcompound of Formula 1 below and including a functional group which isderived from the silane-based compound of Formula 1 below.

According to an embodiment of the present invention, there is provided amodified and conjugated diene-based polymer including a functional groupderived from the compound of Formula 1 below.

In Formula 1,

A¹ and A² are each independently a divalent hydrocarbon group of 1 to 10carbon atoms, which is unsubstituted or substituted with one or at leasttwo selected from the group consisting of an alkyl group of 1 to 10carbon atoms, a cycloalkyl group of 3 to 10 carbon atoms, an alkoxygroup of 1 to 10 carbon atoms, a cycloalkoxy group of 4 to 10 carbonatoms, an aryl group of 6 to 12 carbon atoms, an aryloxy group of 6 to12 carbon atoms, an alkanoyloxy group of 2 to 12 carbon atoms, anarylalkyloxy group of 7 to 13 carbon atoms, an arylalkyl group of 7 to13 carbon atoms, and an alkylaryl group of 7 to 13 carbon atoms,

R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms,

X¹ and X² are each independently a nitrogen-containing heterocyclicgroup which is unsubstituted or substituted with at least one alkylgroup of 1 to 6 carbon atoms, and

n is an integer of 1 to 5.

In addition, according to another embodiment of the present invention,there is provided a method for preparing the modified and conjugateddiene-based polymer, including preparing an active polymer of which atleast one terminal is combined with an alkali metal by polymerizingconjugated diene-based monomers, or an aromatic vinyl-based monomer anda conjugated diene-based monomer in the presence of an organo-alkalimetal compound in a hydrocarbon solvent (step 1); and reacting theactive polymer with a modifier including a silane-based compound ofFormula 1 below (step 2).

In Formula 1,

A¹ and A² are each independently a divalent hydrocarbon group of 1 to 10carbon atoms, which is unsubstituted or substituted with one or at leasttwo selected from the group consisting of an alkyl group of 1 to 10carbon atoms, a cycloalkyl group of 3 to 10 carbon atoms, an alkoxygroup of 1 to 10 carbon atoms, a cycloalkoxy group of 4 to 10 carbonatoms, an aryl group of 6 to 12 carbon atoms, an aryloxy group of 6 to12 carbon atoms, an alkanoyloxy group of 2 to 12 carbon atoms, anarylalkyloxy group of 7 to 13 carbon atoms, an arylalkyl group of 7 to13 carbon atoms, and an alkylaryl group of 7 to 13 carbon atoms,

R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms,

X¹ and X² are each independently a nitrogen-containing heterocyclicgroup which is unsubstituted or substituted with at least one alkylgroup of 1 to 6 carbon atoms, and

n is an integer of 1 to 5.

According to another embodiment of the present invention, there isprovided a modifier including a silane-based compound of Formula 1below.

In Formula 1,

A¹ and A² are each independently a divalent hydrocarbon group of 1 to 10carbon atoms, which is unsubstituted or substituted with one or at leasttwo selected from the group consisting of an alkyl group of 1 to 10carbon atoms, a cycloalkyl group of 3 to 10 carbon atoms, an alkoxygroup of 1 to 10 carbon atoms, a cycloalkoxy group of 4 to 10 carbonatoms, an aryl group of 6 to 12 carbon atoms, an aryloxy group of 6 to12 carbon atoms, an alkanoyloxy group of 2 to 12 carbon atoms, anarylalkyloxy group of 7 to 13 carbon atoms, an arylalkyl group of 7 to13 carbon atoms, and an alkylaryl group of 7 to 13 carbon atoms,

R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms,

X¹ and X² are each independently a nitrogen-containing heterocyclicgroup which is unsubstituted or substituted with at least one alkylgroup of 1 to 6 carbon atoms, and

n is an integer of 1 to 5.

In addition, according to another embodiment of the present invention,there is provided a rubber composition including the modified andconjugated diene-based polymer.

Further, according to another embodiment of the present invention, thereis provided a tire manufactured from the rubber composition.

Advantageous Effects

When used as the modifier of a conjugated diene-based polymer, themodifier according to the present invention may provide a conjugateddiene-based polymer chain with a tertiary amino group having a ringstructure, which has excellent affinity with a filler. As a result, themodified and conjugated diene-based polymer prepared using the modifiermay prevent the agglomeration of a filler and increase thedispersibility of a filler in a rubber composition, thereby improvingprocessability of the rubber composition. In addition, the physicalproperties of a molded article manufactured using the rubber compositionincluding the modified and conjugated diene-based polymer may beimproved, and more particularly, the rolling resistance and abrasionresistance of a tire may be improved in good balance.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in more detail inorder to assist the understanding of the present invention.

It will be understood that words or terms used in the specification andclaims shall not be interpreted as the meaning defined in commonly useddictionaries. It will be further understood that the words or termsshould be interpreted as having a meaning that is consistent with theirmeaning of the technical idea of the invention, based on the principlethat an inventor may properly define the meaning of the words or termsto best explain the invention.

According to an embodiment of the present invention, a modified andconjugated diene-based polymer modified by a modifier including asilane-based compound of Formula 1 below, and including a functionalgroup derived from a silane-based compound of Formula 1 below isprovided.

In Formula 1,

A¹ and A² are each independently a divalent hydrocarbon group of 1 to 10carbon atoms, which is unsubstituted or substituted with one or at leasttwo selected from the group consisting of an alkyl group of 1 to 10carbon atoms, a cycloalkyl group of 3 to 10 carbon atoms, an alkoxygroup of 1 to 10 carbon atoms, a cycloalkoxy group of 4 to 10 carbonatoms, an aryl group of 6 to 12 carbon atoms, an aryloxy group of 6 to12 carbon atoms, an alkanoyloxy group of 2 to 12 carbon atoms, anarylalkyloxy group of 7 to 13 carbon atoms, an arylalkyl group of 7 to13 carbon atoms, and an alkylaryl group of 7 to 13 carbon atoms,

R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms,

X¹ and X² are each independently a nitrogen-containing heterocyclicgroup which is unsubstituted or substituted with at least one alkylgroup of 1 to 6 carbon atoms, and

n is an integer of 1 to 5.

In addition, A¹ and A² may be each independently substituted with one orat least two substituents selected from the group consisting of an alkylgroup of 1 to 4 carbon atoms, a cycloalkyl group of 3 to 6 carbon atoms,an aryl group of 6 to 8 carbon atoms, an arylalkyl group of 7 to 10carbon atoms, and an alkylaryl group of 7 to 10 carbon atoms, and moreparticularly, substituted with an alkyl group of 1 to 4 carbon atoms.

In addition, in Formula 1, R¹ to R⁴ may be each independently a halogengroup such as fluoro, chloro and bromo; or an alkoxy group of 1 to 6carbon atoms such as a methoxy group, an ethoxy group or a propoxygroup, more particularly, a halogen group or an alkoxy group of 1 to 3carbon atoms, further more particularly, a chloro group, a methoxy groupor an ethoxy group.

In addition, in Formula 1, X¹ and X² may be each independently afive-member to eight-member, more particularly, five-member orsix-member heterocyclic group containing at least one, moreparticularly, 1 to 3 nitrogen atoms in a functional group. Particularly,a heterocycloalkyl group such as a piperidinyl group, a piperazinylgroup, a methylpiperazinyl group, a pyrrolidinyl group, an imidazolinylgroup, a pyrrolinyl group, and a triazolinyl group, or a heteroarylgroup such as a pyridinyl group, a pyrazinyl group, a pyrimidinyl group,a pyridazinyl group, and a triazinyl group, more particularly, apiperazinyl group, a triazinyl group or an imidazolinyl group, may beused.

In addition, at least one hydrogen atom in the heterocyclic group may besubstituted with an alkyl group having 1 to 6, more particularly, 1 to 3carbon atoms such as a methyl group, an ethyl group, a propyl group, anisopropyl group, an n-butyl group and a t-butyl group.

In addition, in Formula 1, n may be an integer of 1 to 5, moreparticularly, an integer of 1 or 2.

More particularly, in the silane-based compound of Formula 1, A¹ and A²may be each independently an alkylene group of 1 to 6 carbon atoms,which is unsubstituted or substituted with an alkyl group of 1 to 4carbon atoms, R¹ to R⁴ may be each independently a halogen group or analkoxy group of 1 to 6 carbon atoms, and X¹ and X² may be eachindependently a five-member to eight-member heterocycloalkyl group, moreparticularly, a five-member or six-member heterocycloalkyl groupincluding 1 to 3 nitrogen atoms, which is unsubstituted or substitutedwith an alkyl group of 1 to 3 carbon atoms.

A particular embodiment may include a compound of Formula 1a below.

In Formula 1a, A¹ and A² are each independently an alkylene group of 1to 6 carbon atoms, which is unsubstituted or substituted with at leastone alkyl group of 1 to 4 carbon atoms, R¹ to R⁴ are each independentlya halogen group or an alkoxy group of 1 to 6 carbon atoms, moreparticularly, an alkoxy group of 1 to 4 carbon atoms, further moreparticularly, a methoxy group, and n is an integer of 1 to 5, moreparticularly, an integer of 1 or 2. In addition, R_(a) to R_(d) may beeach independently an alkyl group of 1 to 3 carbon atoms, and p and p′are each independently an integer of 0 to 4.

In addition, in the silane-based compound of Formula 1, A¹ and A² may beeach independently an alkylene group of 1 to 6 carbon atoms, which isunsubstituted or substituted with an alkyl group of 1 to 4 carbon atoms,R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms, and X¹ and X² are each independently a five-member toeight-member heteroaryl group, more particularly, a five-member orsix-member heteroaryl group containing 1 to 3 nitrogen atoms, which issubstituted or unsubstituted.

A particular embodiment may include a compound of Formula 1b below.

In Formula 1b, A¹ and A² are each independently an alkylene group of 1to 6 carbon atoms, which is unsubstituted or substituted with at leastone of an alkyl group of 1 to 4 carbon atoms, R¹ to R⁴ are eachindependently a halogen group or an alkoxy group of 1 to 6 carbon atoms,more particularly, an alkoxy group of 1 to 4 carbon atoms, further moreparticularly, a methoxy group, and n is an integer of 1 to 5, moreparticularly, an integer of 1 or 2. In addition, R_(e) and R_(f) may beeach independently an alkyl group of 1 to 3 carbon atoms, and q and q′are each independently an integer of 0 to 3.

More particularly, the compound of Formula 1 may be a compound ofFormula 2 or Formula 3 below, and one or a mixture of two thereof may beused as a modifier.

In addition, the conjugated diene-based polymer may be a homopolymer ofconjugated diene-based monomers, or a copolymer of a conjugateddiene-based monomer and an aromatic vinyl-based monomer.

In addition, if the modified and conjugated diene-based polymer is acopolymer, the copolymer may be a random copolymer in which structuralunits constituting the copolymer including a structural unit derivedfrom the conjugated diene-based monomer and a structural unit derivedfrom the aromatic vinyl-based monomer are arranged and combined indisorder.

Particularly, the modified and conjugated diene-based polymer may havenarrow molecular weight distribution (Mw/Mn) of 1.1 to 5.0. If themolecular weight distribution of the modified and conjugated diene-basedpolymer is greater than 5.0 or less than 1.1, and when applying thereofto a rubber composition, it is apprehended that tensile properties andviscoelasticity may be degraded. In consideration of remarkableimproving effects of the tensile properties and viscoelasticity of apolymer according to the control of the molecular weight distribution,the molecular weight distribution of the modified and conjugateddiene-based polymer may particularly be from 1.2 to 3.0.

In the present invention, the molecular weight distribution of amodified butadiene-based polymer may be calculated from a ratio (Mw/Mn)of a weight average molecular weight (Mw) to a number average molecularweight (Mn). In this case, the number average molecular weight (Mn) is acommon average of an individual polymer molecular weight, which isobtained by measuring the molecular weights of n polymer molecules,obtaining the total of the molecular weights and dividing the total byn. The weight average molecular weight (Mw) illustrates molecular weightdistribution of a polymer composition. All molecular weight averagevalues may be expressed by gram per mol (g/mol).

In addition, in the present invention, each of the weight averagemolecular weight and the number average molecular weight is apolystyrene converted molecular weight analyzed by gel permeationchromatography (GPC).

In addition, the modified and conjugated diene-based polymer may satisfythe molecular weight distribution conditions and at the same time, mayhave a number average molecular weight (Mn) of 50,000 g/mol to 2,000,000g/mol, more particularly, 200,000 g/mol to 800,000 g/mol. In addition,the modified and conjugated diene-based polymer may have a weightaverage molecular weight (Mw) of 100,000 g/mol to 4,000,000 g/mol, moreparticularly, 300,000 g/mol to 1,500,000 g/mol.

If the weight average molecular weight (Mw) of the modified andconjugated diene-based polymer is less than 100,000 g/mol, or the numberaverage molecular weight (Mn) is less than 50,000 g/mol, and when themodified and conjugated diene-based polymer is applied to a rubbercomposition, it is apprehended that tensile properties may be degraded.In addition, if the weight average molecular weight (Mw) is greater than4,000,000 g/mol, or the number average molecular weight (Mn) is greaterthan 2,000,000 g/mol, the processability of the modified and conjugateddiene-based polymer may be degraded, the workability of a rubbercomposition may be deteriorated, difficulty is shown with mixing andkneading, and sufficient improvement of the physical properties of therubber composition may become difficult.

More particularly, if the modified and conjugated diene-based polymeraccording to an embodiment of the present invention satisfies themolecular weight distribution together with the weight average molecularweight and the number average molecular weight at the same time, andwhen applying thereof to a rubber composition, tensile properties,viscoelasticity and processability with respect to the rubbercomposition may be improved in balance without being biased to any oneof them.

In addition, the modified and conjugated diene-based polymer may have avinyl content of 5 wt % or more, particularly, 10 wt % or more, moreparticularly, 10 wt % to 50 wt %. When the vinyl content is in therange, a glass transition temperature may be controlled in anappropriate range. Accordingly, when applying the modified andconjugated diene-based polymer to tires, physical properties requiredfor tires such as running resistance and braking force may be improved.

In this case, the vinyl content represents the amount of not 1,4-addedbut 1,2-added conjugated diene-based monomer by the percentage based onthe total amount of a conjugated diene-based polymer composed of a vinylgroup-containing monomer or a conjugated diene-based monomer.

In addition, the modified and conjugated diene-based polymer accordingto an embodiment of the present invention has mooney viscosity (MV) of40 to 90, particularly, 60 to 80 at 100° C. With the mooney viscosity inthe range, excellent processability may be attained.

In the present invention, the mooney viscosity may be measured by usinga mooney viscometer, for example, MV2000E of Monsanto Co., Ltd. usingLarge Rotor at a rotor speed of 2±0.02 rpm at 100° C. In this case, aspecimen used was stood at room temperature (23±3° C.) for 30 minutes ormore, and 27±3 g of the specimen was collected and put in a die cavity,and then, Platen was operated for measurement.

According to another embodiment of the present invention, there isprovided a method for preparing the modified and conjugated diene-basedpolymer using a modifier including a silane-based compound of Formula 1.

The preparation method particularly includes a step of preparing anactive polymer of which at least one terminal is combined with an alkalimetal by polymerizing conjugated diene-based monomers, or an aromaticvinyl-based monomer and a conjugated diene-based monomer in the presenceof an organo-alkali metal compound in a hydrocarbon solvent (step 1);and a step of reacting the active polymer with a modifier including asilane-based compound of Formula 1 (step 2).

Step 1 is a step for preparing an active polymer of which at least oneterminal is combined with an alkali metal, and is conducted bypolymerizing conjugated diene-based monomers; or an aromatic vinyl-basedmonomer and a conjugated diene-based monomer in the presence of anorgano-alkali metal compound in a hydrocarbon solvent.

The polymerization in step 1 may use a single type of conjugateddiene-based monomer, or a conjugated diene-based monomer and an aromaticvinyl-based monomer together as monomers. That is, the polymer preparedby the preparation method according to an embodiment of the presentinvention may be a homopolymer of a single type of conjugateddiene-based monomer or a copolymer derived from a conjugated diene-basedmonomer and an aromatic vinyl-based monomer.

The conjugated diene-based monomer is not specifically limited, but maybe at least one selected from the group consisting of, for example,1,3-butadiene, 2,3-dimethyl-1,3-butadiene, piperylene,3-butyl-1,3-octadiene, isoprene and 2-phenyl-1,3-butadiene.

If the conjugated diene-based monomer and the aromatic vinyl-basedmonomer are used together as the monomers, the conjugated diene-basedmonomer may be used in an amount such that the derived unit of theconjugated diene-based monomer is 60 wt % or more, particularly 60 wt %to 90 wt %, more particularly, 60 wt % to 85 wt % in a finally preparedmodified and conjugated diene-based polymer.

The aromatic vinyl-based monomer may be, for example, at least oneselected from the group consisting of styrene, α-methylstyrene,3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 1-vinylnaphthalene,4-cyclohexylstyrene, 4-(p-methylphenyl)styrene, and1-vinyl-5-hexylnaphthalene, without specific limitation.

If the conjugated diene-based monomer and the aromatic vinyl-basedmonomer are used together as the monomers, the aromatic vinyl-basedmonomer may be used in an amount such that an amount of the derived unitof the aromatic vinyl-based monomer in a finally prepared modified andconjugated diene-based polymer is 40 wt % or less, particularly, from 10wt % to 40 wt %, more particularly, from 15 wt % to 40 wt %.

The hydrocarbon solvent is not specifically limited and may be, forexample, at least one selected from the group consisting of n-pentane,n-hexane, n-heptane, isooctane, cyclohexane, toluene, benzene andxylene.

The organo-alkali metal compound may be used from 0.1 mmol to 1.0 mmolbased on 100 g of the total monomers.

The organo-alkali metal compound may be, for example, at least oneselected from the group consisting of methyllithium, ethyllithium,propyllithium, n-butyllithium, s-butyllithium, t-butyllithium,hexyllithium, n-decyllithium, t-octyllithium, phenyllithium, 1-naphthyllithium, n-eicosyl lithium, 4-butylphenyl lithium, 4-tolyl lithium,cyclohexyl lithium, 3,5-di-n-heptylcyclohexyl lithium, 4-cyclopentyllithium, naphthyl sodium, naphthyl potassium, lithium alkoxide, sodiumalkoxide, potassium alkoxide, lithium sulfonate, sodium sulfonate,potassium sulfonate, lithium amide, sodium amide, potassium amide, andlithium isopropylamide, without specific limitation.

The polymerization of step 1 may be conducted by further adding a polaradditive as needed, and the polar additive may be added in an amount of0.001 parts by weight to 1.0 part by weight based on 100 parts by weightof the total monomers. Particularly, the addition amount may be from0.005 parts by weight to 0.5 parts by weight, more particularly, from0.01 parts by weight to 0.3 parts by weight based on 100 parts by weightof the total monomers.

The polar additive may be at least one selected from the groupconsisting of tetrahydrofuran, 2,2-di(2-tetrahydrofuryl)propane, diethylether, dipropyl ether, ethylene dimethyl ether, ethylene dimethyl ether,diethyl glycol, dimethyl ether, tert-butoxy ethoxy ethane,bis(3-dimethylaminoethyl)ether, (dimethylaminoethyl) ethyl ether,trimethylamine, triethylamine, tripropylamine, andtetramethylethylenediamine.

In the preparation method according to an embodiment of the presentinvention, in case of copolymerizing a conjugated diene-based monomerand an aromatic vinyl-based monomer, the difference of the reactionrates therebetween may be compensated by the addition of the polaradditive, thereby attaining easy formation of a random copolymer.

The polymerization of step 1 may be conducted by an adiabaticpolymerization, or a polymerization at a constant temperature.

Here, the adiabatic polymerization means a polymerization methodincluding a step of polymerization using self-generated heat of reactionwithout optionally applying heat after adding an organo-alkali metalcompound.

The polymerization at a constant temperature means a polymerizationmethod by which the temperature of a polymer is kept constant byoptionally applying or taking heat away after adding an organo-alkalimetal compound.

The polymerization may be conducted in a temperature range of −20° C. to200° C., particularly, 0° C. to 150° C., more particularly, 10° C. to120° C.

Step 2 is a modification reaction step of reacting the active polymerand the silane-based modifier of Formula 1 to prepare a modified andconjugated diene-based polymer.

In this case, the silane-based modifier of Formula 1 may be the same asdescribed above. The silane-based modifier of Formula 1 may be used in aratio of 0.1 mol to 2.0 mol with respect to 1 mol of an organo-alkalimetal compound.

The reaction of step 2 is a modification reaction for introducing afunctional group into a polymer, and each reaction may be conducted in atemperature range of 0° C. to 90° C. for 1 minute to 5 hours.

The preparation method according to an embodiment of the presentinvention may further include at least one step of recovering and dryingof solvents and unreacted monomers after step 2, if needed.

Also, according to an embodiment of the present invention, there isprovided a modifier including a silane-based compound of Formula 1below, which may easily introduce a tertiary amino group of a ringstructure, which is a functional group having affinity with a fillerinto a rubber, particularly, a conjugated diene-based polymer.

In Formula 1,

A¹ and A² are each independently a divalent hydrocarbon group of 1 to 10carbon atoms, which is unsubstituted or substituted with one or at leasttwo selected from the group consisting of an alkyl group of 1 to 10carbon atoms, a cycloalkyl group of 3 to 10 carbon atoms, an alkoxygroup of 1 to 10 carbon atoms, a cycloalkoxy group of 4 to 10 carbonatoms, an aryl group of 6 to 12 carbon atoms, an aryloxy group of 6 to12 carbon atoms, an alkanoyloxy group of 2 to 12 carbon atoms, anarylalkyloxy group of 7 to 13 carbon atoms, an arylalkyl group of 7 to13 carbon atoms, and an alkylaryl group of 7 to 13 carbon atoms,

R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms,

X¹ and X² are each independently a nitrogen-containing heterocyclicgroup which is unsubstituted or substituted with at least one alkylgroup of 1 to 6 carbon atoms, and

n is an integer of 1 to 5.

In the modifier according to an embodiment of the present invention, ifthe silane compound of the structure is applied as the modifier of aconjugated diene-based polymer, a tertiary amino group of a ringstructure, having even stronger affinity with respect to a filler in arubber composition, such as silica and carbon black may be provided.Accordingly, a modified and conjugated diene-based polymer having afunctional group derived from the silane-based compound may showexcellent affinity with respect to a filler, when applied to a rubbercomposition, and as a result, the agglomeration of a filler in a rubbercomposition may be prevented and the dispersibility of a filler may beincreased, thereby improving the processability of a rubber composition.In addition, the physical properties of a molded article manufacturedusing the rubber composition may be improved. Particularly, the tertiaryamino group of a ring structure is combined with filler particles todecrease the mobility of the terminal of a modified and conjugateddiene-based polymer, thereby decreasing hysteresis loss when applied toa rubber composition for a tire. Through this, the rolling resistanceand abrasion resistance of a tire may be improved with good balance.

The modifier according to an embodiment of the present invention may bea modifier for modifying the structure, properties and physicalproperties of a rubber, particularly, a modifier for a conjugateddiene-based polymer such as a butadiene-based polymer and astyrene-butadiene copolymer.

Further, according to another embodiment of the present invention, thereis provided a rubber composition including the modified and conjugateddiene-based polymer.

Since the rubber composition includes the modified and conjugateddiene-based polymer, the physical properties of a molded article may beimproved, and particularly, rolling resistance and abrasion resistancemay be improved with good balance.

Particularly, the rubber composition may include the modified andconjugated diene-based polymer in an amount of 0.1 wt % to 100 wt %,particularly, 10 wt % to 100 wt %, more particularly 20 wt % to 90 wt %.If the amount of the modified and conjugated diene-based polymer is lessthan 0.1 wt %, improving effects of fuel efficiency, abrasion resistanceand crack resistance of a molded article, for example, a tiremanufactured by using the rubber composition may be insignificant.

In addition, the rubber composition may further include other rubbercomponents, if necessary, in addition to the modified and conjugateddiene-based polymer, and, in this case, the rubber component may beincluded in an amount of 90 wt % or less based on the total amount ofthe rubber composition. Specifically, the rubber composition may includethe rubber component in an amount of 1 part by weight to 900 parts byweight based on 100 parts by weight of the modified and conjugateddiene-based copolymer.

The rubber component may be a natural rubber or a synthetic rubber, andthe rubber component may be, for example, a natural rubber (NR)including cis-1,4-polyisoprene; a modified natural rubber which isobtained by modifying or purifying a common natural rubber, such as anepoxidized natural rubber (ENR), a deproteinized natural rubber (DPNR),and a hydrogenated natural rubber; and a synthetic rubber such as astyrene-butadiene copolymer (SBR), a polybutadiene (BR), a polyisoprene(IR), a butyl rubber (IIR), an ethylene-propylene copolymer, apolyisobutylene-co-isoprene, a neoprene, a polyethylene-co-propylene), apoly(styrene-co-butadiene), a poly(styrene-co-isoprene), apoly(styrene-co-isoprene-co-butadiene), a poly(isoprene-co-butadiene), apoly(ethylene-co-propylene-co-diene), a polysulfide rubber, an acrylrubber, a urethane rubber, a silicone rubber, an epichlorohydrin rubber,a butyl rubber, a halogenated butyl rubber, and any one or a mixture ofat least two thereof may be used.

In addition, the rubber composition may include 0.1 parts by weight to150 parts by weight of a filler based on 100 parts by weight of themodified and conjugated diene-based polymer.

The filler may particularly be a silica-based filler or a carbonblack-based filler, and one or a mixture of two thereof may be used.

More particularly, the filler may be silica, more particularly, wetsilica (hydrated silicate), dry silica (anhydrous silicate), calciumsilicate, aluminum silicate, or colloid silica. More particularly, thefiller may be wet silica which has the most significant improvingeffects of destruction characteristics and compatible effects of wetgrip characteristics.

Meanwhile, if a silica-based filler is used as the filler, a silanecoupling agent may be used together for the improvement of reinforcingand low exothermic properties.

The silane coupling agent may particularly includebis(3-triethoxysilylpropyl)tetrasulfide,bis(3-triethoxysilylpropyl)trisulfide,bis(3-triethoxysilylpropyl)disulfide,bis(2-triethoxysilylethyl)tetrasulfide,bis(3-trimethoxysilylpropyl)tetrasulfide,bis(2-trimethoxysilylethyl)tetrasulfide,3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane,2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane,3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide,3-triethoxysilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide,2-triethoxysilylethyl-N,N-dimethylthiocarbamoyltetrasulfide,3-trimethoxysilylpropylbenzothiazolyltetrasulfide,3-triethoxysilylpropylbenzolyltetrasulfide,3-triethoxysilylpropylmethacrylatemonosulfide,3-trimethoxysilylpropylmethacrylatemonosulfide,bis(3-diethoxymethylsilylpropyl)tetrasulfide,3-mercaptopropyldimethoxymethylsilane,dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyltetrasulfide, ordimethoxymethylsilylpropylbenzothiazolyltetrasulfide, and any one or amixture of at least two thereof may be used. More particularly, thesilane coupling agent may be bis(3-triethoxysilylpropyl)polysulfide or3-trimethoxysilylpropylbenzothiazyltetrasulfide in consideration of theimproving effect of reinforcing properties.

In addition, in the rubber composition according to an embodiment of thepresent invention, a modified and conjugated diene-based polymer inwhich a functional group having high affinity with a silica-based filleris introduced into an active part is used as a rubber component, and themixing amount of a silane coupling agent may be smaller than a commoncase. In particular, the silane coupling agent may be used in an amountof 1 part by weight to 20 parts by weight based on 100 parts by weightof the silica-based filler. With the amount used in the above range,effects as a coupling agent may be sufficiently exhibited, and thegelation of a rubber component may be prevented. More particularly, thesilane coupling agent may be used in an amount of 5 parts by weight to15 parts by weight based on 100 parts by weight of silica.

In addition, the rubber composition according to an embodiment of thepresent invention may be sulfur crosslinkable, and so may furtherinclude a vulcanizing agent.

The vulcanizing agent may be particularly a sulfur powder and may beincluded in an amount of 0.1 parts by weight to 10 parts by weight basedon 100 parts by weight of a rubber component. With the amount used inthe above range, elasticity and strength required for a vulcanizedrubber composition may be secured, and at the same time, a low fuelconsumption ratio may be attained.

In addition, the rubber composition according to an embodiment of thepresent invention may further include various additives used in a commonrubber industry in addition to the above components, particularly, avulcanization accelerator, a process oil, a plasticizer, an antiagingagent, a scorch preventing agent, a zinc white, stearic acid, athermosetting resin, or a thermoplastic resin.

The vulcanization accelerator is not specifically limited and mayparticularly include thiazole-based compounds such as2-mercaptobenzothiazole (M), dibenzothiazyldisulfide (DM), andN-cyclohexyl-2-benzothiazylsulfenamide (CZ), or guanidine-basedcompounds such as diphenylguanidine (DPG). The vulcanization acceleratormay be included in an amount of 0.1 parts by weight to 5 parts by weightbased on 100 parts by weight of the rubber component.

In addition, the process oil acts as a softener in a rubber compositionand may particularly include a paraffin-based, naphthene-based, oraromatic compound. More particularly, an aromatic process oil may beused in consideration of tensile strength and abrasion resistance, and anaphthene-based or paraffin-based process oil may be used inconsideration of hysteresis loss and properties at low temperature. Theprocess oil may be included in an amount of 100 parts by weight or lessbased on 100 parts by weight of the rubber component. With theabove-described amount, the deterioration of tensile strength and lowexothermic properties (low fuel consumption ratio) of the vulcanizedrubber may be prevented.

In addition, the antiaging agent may particularly includeN-isopropyl-N′-phenyl-p-phenylenediamine,N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine,6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, or a condensate ofdiphenylamine and acetone at a high temperature. The antiaging agent maybe used in an amount of 0.1 parts by weight to 6 parts by weight basedon 100 parts by weight of the rubber component.

The rubber composition according to an embodiment of the presentinvention may be obtained by mulling using a mulling apparatus such as abanbury mixer, a roll, and an internal mixer according to a mixingprescription. In addition, a rubber composition having low exothermicproperties and good abrasion resistance may be obtained by avulcanization process after a molding process.

Therefore, the rubber composition may be useful to the manufacture ofeach member of a tire such as a tire tread, an under tread, a side wall,a carcass coating rubber, a belt coating rubber, a bead filler, and abead coating rubber, or to the manufacture of rubber products in variousindustries such as a dustproof rubber, a belt conveyor, and a hose.

Further, according to another embodiment of the present invention, thereis provided a molded article and a tire manufactured using the rubbercomposition.

Further, according to another embodiment of the present invention, thereis provided a silane-based compound of Formula 1 useful for preparingthe modifier.

Hereinafter, the present invention will be explained in particularreferring to embodiments and experimental embodiments. However, thefollowing embodiments and experimental embodiments are only for theillustration of the present invention, and the scope of the presentinvention is not limited thereto.

Example 1

To a 20 L autoclave reactor, 270 g of styrene, 710 g of 1,3-butadiene,5,000 g of n-hexane, and 1.3 g of 2,2-di(2-tetrahydrofuryl)propane as apolar additive were added, and the internal temperature of the reactorwas elevated to 40° C.

When the internal temperature of the reactor reached 40° C., 4 mmol ofn-butyllithium was injected into the reactor, and an adiabatic reactionwith heating was performed. After about 20 minutes, 20 g of1,3-butadiene was injected for capping the terminal of SSBR withbutadiene. After 5 minutes, 4 mmol of a compound of Formula 2 below wasinjected as a modifier, and reaction was conducted for 15 minutes. Then,the polymerization reaction was quenched using ethanol, and 5 ml of ahexane solution in which 0.3 wt % of a butyrate hydroxytoluene (BHT)antioxidant was dissolved was added thereto. The polymer thus obtainedwas injected into hot water heated with steam, stirred to removesolvents, and roll dried to remove remaining solvents and water toprepare a modified styrene-butadiene copolymer.

Example 2

A modified styrene-butadiene copolymer was prepared by conducting thesame method described in Example 1 except for conducting modificationreaction by injecting 4 mmol of a compound of Formula 3 below instead ofthe compound of Formula 2 in Example 1 as a modifier.

Comparative Example 1

A modified styrene-butadiene copolymer was prepared by conducting thesame method described in Example 1 except for conducting modificationreaction by injecting 4 mmol of tetraethoxysilane (TEOS) instead of thecompound of Formula 2 in Example 1 as a modifier.

Experimental Example 1

A weight average molecular weight (Mw), a number average molecularweight (Mn), polydispersity index (PDI), styrene derived structural unitand vinyl contents, and mooney viscosity (MV) were measured for each ofthe modified styrene-butadiene copolymers prepared in Examples 1 and 2and Comparative Example 1. The results are shown in Table 1 below.

1) Analysis of Styrene Derived Structural Unit and Vinyl Contents

The styrene derived structural unit (SM) and vinyl contents in eachcopolymer were measured using nuclear magnetic resonance (NMR) analysis.

2) Analysis of Molecular Weights

The weight average molecular weight (Mw) and the number averagemolecular weight (Mn) were measured by gel permeation chromatography(GPC) analysis in conditions of 40° C. In this case, the two columns ofPLgel Olexis and one column of PLgel mixed-C of Polymer Laboratories Co.Ltd. were used in combination, and newly replaced columns were all mixedbed type columns. In addition, polystyrene (PS) was used as a GPCstandard material for calculating the molecular weight. Polydispersityindex (PDI) was calculated from the ratio (Mw/Mn) of the weight averagemolecular weight (Mw) and the number average molecular weight (Mn)measured by the above method.

3) Analysis of Mooney Viscosity

The mooney viscosity of each copolymer was measured by using MV-2000(Alpha Technologies Co., Ltd.) at 100° C. for 4 minutes afterpre-heating two specimens, of which amount was 15 g or more each, for 1minute.

TABLE 1 Comparative Example 1 Example 2 Example 1 Modifier amount used(mmol) 4 4 4 Mooney viscosity (MV) 67 69 98 NMR Styrene derivedstructural 27.0 26.9 27.2 unit content (wt % based on total polymeramount) Vinyl content (wt % based 42.9 42.7 42.7 on total polymeramount) GPC Mn (×10⁴ g/mol) 12.6 12.2 14.8 Mw (×10⁴ g/mol) 14.4 14.121.6 PDI (Mw/Mn) 1.14 1.16 1.46

Experimental Example 2

In order to comparatively analyze the physical properties of a rubbercomposition including each copolymer of Examples 1 and 2 and ComparativeExample 1 and a molded article manufactured therefrom, tensileproperties and viscoelasticity properties were measured.

1) Preparation of Rubber Composition

Each rubber composition was prepared via a first stage mulling, a secondstage mulling and a third stage mulling. In this case, the amounts usedof materials excluding a modified styrene-butadiene copolymer were shownbased on 100 parts by weight of the modified styrene-butadienecopolymer. In the first stage mulling, 100 parts by weight of eachcopolymer, 70 parts by weight of silica, 11.02 parts by weight ofbis(3-triethoxysilylpropyl)tetrasulfide as a silane coupling agent,33.75 parts by weight of a process oil (TDAE), 2.0 parts by weight of anantiaging agent (TMDQ), 2.0 parts by weight of an antioxidant, 3.0 partsby weight of zinc oxide (ZnO), 2.0 parts by weight of stearic acid, and1.0 part by weight of wax were mixed and mulled under conditions of 80rpm by using a banbury mixer equipped with a temperature controllingapparatus. In this case, the temperature of the mulling apparatus wascontrolled, and a first compound mixture was obtained at a dischargetemperature of 140° C. to 150° C. In the second stage mulling, the firstcompound mixture was cooled to room temperature, and 1.75 parts byweight of a rubber accelerator (CZ), 1.5 parts by weight of a sulfurpowder, and 2.0 parts by weight of a vulcanization accelerator wereadded to the mulling apparatus and mixed at a temperature of 60° C. orless to obtain a second compound mixture. Then, the second compoundmixture was molded at the third stage mulling, and vulcanized at 180° C.for t90+10 minutes using a vulcanization press to prepare eachvulcanized rubber.

2) Tensile Properties

The tensile properties were measured by manufacturing each specimen(thickness of 25 mm, length of 80 mm) and measuring tensile strengthwhen broken and tensile stress when elongated by 300% (300% modulus) ofeach specimen according to an ASTM 412 tensile test method.Particularly, a Universal Test machine 4204 tensile tester (Instron Co.,Ltd.) was used, and measurement was performed at room temperature at arate of 50 cm/min, to obtain a tensile strength value and a tensilestress value when elongated by 300%.

3) Viscoelasticity Properties

The viscoelasticity properties were measured by using a dynamicmechanical analyzer (TA Co., Ltd.). Tan 5 was measured by changingdeformation at each measurement temperature (0° C. to 60° C.) with atwist mode and a frequency of 10 Hz. Payne effect (^(Δ)G′) was shown asthe difference between a minimum value and a maximum value atdeformation of 0.28% to 40%, and if the Payne effect decreases, it meansthat dispersibility of a filler is excellent. In addition, if the tan 5at a high temperature of 60° C. is low, it means that hysteresis loss issmall, and low rolling resistance (fuel consumption ratio) is good.

TABLE 2 Comparative Example 1 Example 2 Example 1 300% modulus 150 147120 (Kgf/cm²) Tensile strength 230 220 167 (Kgf/cm²) ΔG′ 0.52 0.51 1.20tan δ @ 0° C. 1.167 1.197 0.942 tan δ @ 60° C. 0.082 0.085 0.124

Referring to the experimental results, the rubber composition includingthe modified styrene-butadiene copolymer of Example 1 or 2, which wasmodified using a modifier according to the present invention, wasexcellent in terms of all the properties of tensile strength,viscoelasticity and processability when compared to those of ComparativeExample 1.

1. A modified and conjugated diene-based polymer comprising a functionalgroup which is derived from a silane-based compound of the followingFormula 1:

in Formula 1, A¹ and A² are each independently a divalent hydrocarbongroup of 1 to 10 carbon atoms, which is unsubstituted or substitutedwith one or at least two selected from the group consisting of an alkylgroup of 1 to 10 carbon atoms, a cycloalkyl group of 3 to 10 carbonatoms, an alkoxy group of 1 to 10 carbon atoms, a cycloalkoxy group of 4to 10 carbon atoms, an aryl group of 6 to 12 carbon atoms, an aryloxygroup of 6 to 12 carbon atoms, an alkanoyloxy group of 2 to carbonatoms, an arylalkyloxy group of 7 to 13 carbon atoms, an arylalkyl groupof 7 to 13 carbon atoms, and an alkylaryl group of 7 to 13 carbon atoms,R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms, X¹ and X² are each independently anitrogen-containing heterocyclic group which is unsubstituted orsubstituted with at least one alkyl group of 1 to 6 carbon atoms, and nis an integer of 1 to
 5. 2. The modified and conjugated diene-basedpolymer of claim 1, wherein in Formula 1, X¹ and X² are eachindependently a five-member to eight-member heterocyclic groupcontaining 1 to 3 nitrogen atoms, which is unsubstituted or substitutedwith at least one alkyl group of 1 to 3 carbon atoms.
 3. The modifiedand conjugated diene-based polymer of claim 1, wherein in Formula 1, A¹and A² are each independently an alkylene group of 1 to 6 carbon atomswhich is unsubstituted or substituted with at least one alkyl group of 1to 4 carbon atoms, R¹ to R⁴ are each independently a halogen group or analkoxy group of 1 to 6 carbon atoms, and X¹ and X² are eachindependently a five-member or six-member heterocycloalkyl group orheteroaryl group containing 1 to 3 nitrogen atoms, which isunsubstituted or substituted with at least one alkyl group of 1 to 3carbon atoms.
 4. The modified and conjugated diene-based polymer ofclaim 1, wherein the silane-based compound of Formula 1 is a compound ofthe following Formula 1a:

in Formula 1a, A¹ and A² are each independently an alkylene group of 1to 6 carbon atoms, which is unsubstituted or substituted with at leastone of an alkyl group of 1 to 4 carbon atoms, R¹ to R⁴ are eachindependently a halogen group or an alkoxy group of 1 to 6 carbon atoms,R_(a) to R_(d) are each independently an alkyl group of 1 to 3 carbonatoms, n is an integer of 1 to 5, and p and p′ are each independently aninteger of 0 to
 4. 5. The modified and conjugated diene-based polymer ofclaim 1, wherein the silane-based compound of Formula 1 is a compound ofthe following Formula 1b:

in Formula 1b, A¹ and A² are each independently an alkylene group of 1to 6 carbon atoms, which is unsubstituted or substituted with at leastone of an alkyl group of 1 to 4 carbon atoms, R¹ to R⁴ are eachindependently a halogen group or an alkoxy group of 1 to 6 carbon atoms,R_(e) and R_(f) are each independently an alkyl group of 1 to 3 carbonatoms, n is an integer of 1 to 5, and q and q′ are each independently aninteger of 0 to
 3. 6. The modified and conjugated diene-based polymer ofclaim 1, wherein the silane-based compound of Formula 1 is at least oneamong the following Formula 2 and Formula 3:


7. The modified and conjugated diene-based polymer of claim 1, whereinthe modified and conjugated diene-based polymer is a homopolymer ofconjugated diene-based monomers, or a modified polymer of a copolymer ofa conjugated diene-based monomer and an aromatic vinyl-based monomer. 8.The modified and conjugated diene-based polymer of claim 1, wherein themodified and conjugated diene-based polymer has a mooney viscosity at100° C. is from 40 to
 90. 9. A method for preparing the modified andconjugated diene-based polymer of claim 1, the method comprising:preparing an active polymer of which at least one terminal is combinedwith an alkali metal by polymerizing conjugated diene-based monomers, oran aromatic vinyl-based monomer and a conjugated diene-based monomer inthe presence of an organo-alkali metal compound in a hydrocarbon solvent(step 1); and reacting the active polymer with a modifier comprising asilane-based compound of the following Formula 1 (step 2):

in Formula 1, A¹ and A² are each independently a divalent hydrocarbongroup of 1 to 10 carbon atoms, which is unsubstituted or substitutedwith one or at least two selected from the group consisting of an alkylgroup of 1 to 10 carbon atoms, a cycloalkyl group of 3 to 10 carbonatoms, an alkoxy group of 1 to 10 carbon atoms, a cycloalkoxy group of 4to 10 carbon atoms, an aryl group of 6 to 12 carbon atoms, an aryloxygroup of 6 to 12 carbon atoms, an alkanoyloxy group of 2 to carbonatoms, an arylalkyloxy group of 7 to 13 carbon atoms, an arylalkyl groupof 7 to 13 carbon atoms, and an alkylaryl group of 7 to 13 carbon atoms,R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms, X¹ and X² are each independently anitrogen-containing heterocyclic group which is unsubstituted orsubstituted with at least one alkyl group of 1 to 6 carbon atoms, and nis an integer of 1 to
 5. 10. The method for preparing the modified andconjugated diene-based polymer of claim 9, wherein a polar additive isfurther added during polymerizing.
 11. A modifier comprising asilane-based compound of the following Formula 1:

in Formula 1, A¹ and A² are each independently a divalent hydrocarbongroup of 1 to 10 carbon atoms, which is unsubstituted or substitutedwith one or at least two selected from the group consisting of an alkylgroup of 1 to 10 carbon atoms, a cycloalkyl group of 3 to 10 carbonatoms, an alkoxy group of 1 to 10 carbon atoms, a cycloalkoxy group of 4to 10 carbon atoms, an aryl group of 6 to 12 carbon atoms, an aryloxygroup of 6 to 12 carbon atoms, an alkanoyloxy group of 2 to 12 carbonatoms, an arylalkyloxy group of 7 to 13 carbon atoms, an arylalkyl groupof 7 to 13 carbon atoms, and an alkylaryl group of 7 to 13 carbon atoms,R¹ to R⁴ are each independently a halogen group or an alkoxy group of 1to 6 carbon atoms, X¹ and X² are each independently anitrogen-containing heterocyclic group which is unsubstituted orsubstituted with at least one alkyl group of 1 to 6 carbon atoms, and nis an integer of 1 to
 5. 12. A rubber composition comprising themodified and conjugated diene-based polymer according to claim
 1. 13.The rubber composition of claim 12, wherein the rubber compositionfurther comprises a filler in an amount of 0.1 parts by weight to 150parts by weight based on 100 parts by weight of the modified andconjugated diene-based polymer.
 14. The rubber composition of claim 13,wherein the filler is a silica-based filler.
 15. A tire manufacturedfrom the rubber composition of claim 12.